Essential Elements of OS OS Bare Bones Not all computers have operating systems. The computer that controls the microwave oven in your kitchen, for example, doesn't need an operating system. It has one set of tasks to perform, very straightforward input to expect (a numbered keypad and a few pre-set buttons) and simple, never-changing hardware to control. For a computer like this, an operating system would be unnecessary baggage, driving up the development and manufacturing costs significantly and adding complexity where none is required. Instead, the computer in a microwave oven simply runs a single hard-wired program all the time. For other devices, an operating system creates the ability to: • serve a variety of purposes • interact with users in more complicated ways • keep up with needs that change over time All desktop computers have operating systems. The most common are the Windows family of operating systems developed by Microsoft , the M...